Talk Talk is a weird one, in that I think it provides an excellent service, but have done all of the communication via its forum - which I find excellent.
It's rather like Three, where you get great support via Twitter but poor support over the phone (a call centre in India).
But, ultimately, I want a good Internet service and this is where TalkTalk excels because you're able to talk to people online that can do proper account checks, make profile changes and more.
As such, you might find that you have a slow, but stable, Internet connection - but that doesn't mean going elsewhere would be any better (same exchange, cabling etc). However, if you ask to remove the line management and fix a faster profile, they will and then you can see speeds shoot up - with the understanding that it might be a bit less reliable and result in the occasional dropped connection.
I accept this, and get almost 8Mbps where I'd only have got 4 before. I might have to reboot the modem once a fortnight, or occasionally see that it reconnected by itself. No real issue.
By contrast, I couldn't see some other companies having this level of direct access and that would be a step backwards for me. It's like having forums like this, where you can speak to people who know a lot more than you'd get calling up a rail enquiries service.